The improvement of the driving comfort of motor vehicles is of constant concern to manufacturers and is an incentive for them to provide vehicles with an adjustable steering column allowing the position of the steering wheel to be adapted to the morphology of the driver.
This adaptation can be effected in the vertical plane and/or along the axis of the steering column. In the first case, the steering shaft carrying the steering wheel is rotatably mounted in a column body which is capable of pivoting about a horizontal axis. In the second case, the steering shaft is constructed in two parts mounted telescopically relative to one another Adjustment devices control the displacements and hold the column in the desired position.
At present, these adjustment devices are generally controlled manually, allowing them to be of robust and reliable construction. Indeed, although users are desirous of having at their disposal servo adjustment controls and, in particular, electrically powered adjustment controls, the construction of such controls has proven difficult by reason, in particular, of the forces to which the steering column of the vehicle is subjected.